Catalytic process for converting hydrocarbons

ABSTRACT

For converting hydrocarbons, particularly by cracking and dehydrogenation, react hydrocarbons at 225*-800*C, particularly 300*-600*C, in contact with a soluble catalyst in liquid phase, said catalyst comprising a compound of a metal of group Ib, IIb, IVa, Va, VIa, VIIa or VIII and a reducing agent, particularly one of formula Al Hn X3 n with n 1 or 2, X OR, NR2, NHR or SR, R being a monovalent organic radical, or one of formula Me (Al HmX&#39;&#39;4 m )p wherein m is 1, 2 or 3, p is the valence of Me,i.e., of a metal of group Ia or IIa, and X&#39;&#39; is R, OR, NR2, NHR or SR.

United States Patent [1 1 Lassau et a].

[73] Assignee: lnstitut Francois du Petrole, des Carburants et Luhrifiants, Rueil Malmaison, France [22] Filed: Oct. 27, 1970 [21] Appl. No.: 84,496

[30] Foreign Application Priority Data Nov. 5, 1969 France 6938132 [52] US. Cl 208/124, 208/114, 208/122, 208/123, 260/668 D 51 Int. Cl C10g 11/02 [58] Field of Search 208/114, 122, 123, 208/124; 260/668 D [56] References Cited UNITED STATES PATENTS 2,369,734 2/1945 Heard 208/123 X Nov. 20, 1973 Primary ExaminerDaniel E. Wyman Assistant Examiner-P. F. Shaver Attorney-Millen, Raptes and White [57] ABSTRACT For converting hydrocarbons, particularly by cracking and dehydrogenation, react hydrocarbons at 225-800C, particularly 300-600C, in contact with a soluble catalyst in liquid phase, said catalyst comprising a compound of a metal of group lb, lIb, IVa, Va, VIa, VIIa or V111 and a reducing agent, particularly one of formula Al 11,, X with n 1 or 2, X OR, NR NHR or SR, R being a monovalent organic radical, or one of formula Me [Al H,,,X, ]p wherein m is l, 2 or 3, p is the valence of Me,i.e., of a metal of group 1a or 1111, and X is R, OR, NR NHR or SR.

22 Claims, No Drawings CATALYTIC PROCESS FOR CONVERTING HYDROCARBONS This invention relates to a new process for converting hydrocarbons by contacting a hydrocarbon feed charge with a catalyst. This conversion process includes particularly such reactions as hydrocarbons cracking and dehydrogenating.

By cracking, there is meant obtaining molecules lighter than those of the feedstock. This operation mainly consists of breaking carbon-carbon bonds, and also includes in variable proportions, such reactions as dehydrogenation, hydrogen transfer and isomerization of the carbon skeleton of the molecules.

The dehydrogenation results in hydrocarbons of the same number of carbon atoms, however with a lower hydrogen content.

When carried out at high temperature, these reactions are well-known by those skilled in the art and are carried out, in practice, at temperatures from 450 to l,400C,'according to the type of charge and the desired degree of conversion. Heterogeneous catalysts may be used, in particular simple oxides of acid character or metals on carriers.

This invention describes the use, in this type of reactions, of a new catalyst soluble in hydrocarbons, which may be entirely dissolved, partially or completely, in the charge before it enters the reactor.

The catalyst which may be used according to this invention results from contacting a metal compound with a reducing agent.

The metal compound may be'any salt ofa metal from groups lb, llb, lVa, Va, Vla, Vlla and VIII, such as titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, molybdenum, ruthenium, rhodium, palladium, tungsten, iridium or platinum. The associated ions may be either inorganic, such as the hydrides, halogenides or sulfocyanides ions, or organic such as for example an alkoxide ion, the acetylacetonate ion, the cyclopentadienyl ion, the sulfonate ion, for example the camphorsulfonate ion, or an ion from an organic acid, for example stearic acid, 2-ethyl hexanoic acid or a naphthenic acid. Optionally the metal may be coordinated with electron-donor ligands, such as ethers, amines, phosphines, arsines and stibines. I c

The following are examples of useful compounds: cobalt bromide, iron, cobalt or nickel naphthenate, oleate, stearate or octoate, irrespective of their content of metal, ferric chloride, chromium acetylacetonate, dichlorodicyclopentadienyl titanium, bis-tricyclohexyl phosphine dibromocobalt, and manganese chloride.

The reducing. agent is preferably an organo aluminum derivative having at least one hydrogenaluminum or carbon-aluminum bond. Preferred agents are those of the two following formulae:

1. those of the general formula A] H,,X in which n is l or 2 and the X groups, either identical or not, are OR, NR NHR or SR groups wherein R is an optionally substituted, linear or cyclic monovalent organic radical which may contain heteroatoms, for example oxygen, sulfur, nitrogen atoms and even metals. R contains for example I to carbon atoms and is for example alkyl, cycloalkyl or aryl. Alkyl of 2-20 carbon atoms is preferred.

When n is l, the two X groups may be linked to form an AZB group in which A and B are alkylene radicals and Z is an oxygen or sulfur atom, an alkylene group, a NH group or a N-hydrocarbyl group;

2. those of the general formula ME[AL H X', ,,,]p in which m is 1, 2 or 3; Me is a monoor a di-valent metal from group I A or ll A andp is the valence of this metal. The X groups, either identical or not, are R, OR, NR NHR or SR groups in which R is as hereinbefore defined. Two X groups may be linked together as described hereinbefore with respect to X.

As reducing agents of the'above formulae, the following may be named by way of examples:

LiALH (O-tert-butyl) NaAlH (O-tert.-butyl) AIH (O-tert-butyl) NaAll-l (C H NaAll-l (i'so-butyl) NAAIH (OCH CH OCH NaAll-l (O-tert-butyl) LiAll-l (iso-butyl) NaHzAl LiAll-l(C l-l and NaAlH (OC H Other useful although less preferred and less active reducing agents are those of the formula:

AlR OR or AIRQ;

wherein the R groups, either identical or not, are defined as before and contain each at least 2 carbon atoms. The R groups are hydrogen or halogen atoms or hydrocarbyl groups containing each from 2 to 20 carbon atoms, at least one'of which being a hydrocarbyl radical.

As examples the following are mentioned: ethoxydiethyl aluminum, triethylaluminum, tert.butoxy diethyl aluminum, ethyl aluminum sesquichloride, and di-n.butyl aluminum hydride- The reducing agent may be contacted with the metal compound, when manufacturing the catalyst, either inside or outside, the reaction medium. In the latter case, the reduction may be carried out at a lower temperature, and it is possible to use reducing agents which can hardly be used in situ, for example some metals or metal compounds which can result in soluble catalysts,

although they are not soluble alone; some organometaltoo unstable to be used easily in to the metal compound may be varied. It is usuallyselected from 0.5 to 20, and preferably from I to 6.

Oxygen acts as an inhibitor to the reduction of the metal compound. However, the latter may be carried out in a nitrogen, argon or methane atmosphere and preferably in a hydrogen atmosphere. Although solvents may be used, the preferred agents are the hydrocarbon reactants, such as paraffins or cycloparaffins.

When a certaln amount of olefin is present during the catalyst manufacture, the resulting catalyst is highly actlYe but a low content of free carbon.

EXAMPLES 4 to 9 Example 3 has been repeated with other catalysts.

5 The results are summarized in the following table:

80 percent at 310C has been treated as in example 1. The conversion rate was 40 percent to gasoline and gas. The products had Conversion Molar ratio Al to gas and compound/metal gasoline, Example Metal compound Al compound compound percent 4 Nickel stearate Na A1H(O C3115): 1. 5 35 5 Chromium stearato Li AlH(O-tert-buty1)3 4 30 6 'Ii (cyclopenadiono)2Cl2. Na AlIlfliso-Cdhh... G 2!) 7 Cobalt octoate AlII(O-tertbuty1)2 1,5 32 s Ferrous stearatc Al (021192002115 4 11- Cobalt stcuratc Al (iso-butyl): s 1

taining 5-20 carbon atoms. Alkylaromatic hydrocar- 15 EXAMPLE l0 gf igifi fi igg g g ggfg z i zf the The catalyst has been manufactured by reacting 0.6 A h drocarbon mixture may also be used for exammillimol' of Na A] HAO-tembutyl) (O furfuryl) with 16 a yetroleum cut Aromatic h drocarbons ma be 0.2 millimol. of cobalt naphthenate. This solution has s without y inconvenient; y been injected into 100 ccm of previously purified tetrap The concentration of metal may be as low as 0.0001 20 hydronaphthalene whqse chiomatographic analysis in g per 100 g offeed to be treated. The preferred concengas phase showsa no Impurity The whole has been trations are between 0 001 and l g of metal per kg of heated up to 400 C under 2 atmospheres of hydrogen feedstock initial pressure. After 2 hours of reaction, the product The reaction is carried out in liquid phase, optionally 5 2 12 5: f down andanalysed by gas phase chmin the presence ofa vapor phase. Oxygen is detrimental Thigs g Showed the resence of 20 ercem of to the catalyst; however the reaction may be carried y p out in the presence of Such gases as y g nitrogen naphthalene which has also been characterized by its argon or a light hydrocarbon Such as metharle ethane: solid derivative with picric acid. The yield with respect or propane. Hydrogen is beneficial when relatively sati iz gf i s tetrahydronaphthalene was practically urated products or a long life of the catalyst are deq sired. EXAMPLE 10 his The following examples are given for illustrative pur- Example 10 has been repeated, however without cap poses alyst, under identical experimental conditions. The re- EXAMPLE 1 sulting product is unconverted tetrahydronaphthalene 0.005 part by weight ofa catalyst consisting of cobalt without naphthalenestearate and Na Al H, (O-tert-butyl) (O-tetrahydrofur- EXAMPLE l0 ter furyl) whose molar ratio Al/Co is 2, is introduced into 100 parts by weight of cetane preheated to 420C 40 Example 10 has been repeated with cobalt naphthen- After about 90 minutes the initial pressure of 2 bars is ate P fvlthout compound, under increased to 15 haw 19 percent of cetane have been CX'WISC identical conditions. Tetrahydronaphthalene cracked and the resulting liquid product consisted, in Minot been convertedaddition to unconverted cetane, of 32 percent C 34 EXAMPLE 1 1 percent Cg"-C 2, and 34 percent C -C hydrocarbons.

. Example 10 has been repeated, however cobalt naph- EXAMPLE l thenate has been substituted with nickel stearate, under Example I has been repeated however without otherwise identical conditions. 13 percent of naphthaminum compound The conversion was only 6 percent lene were present in the reaction products, as shown by chromatographic analysis. EXAMPL 1 te The invention is not limited to the particular condi- Example 1 has been repeated, however without cata- Hons and reacnons shown, before: lyst. A purely thermal reaction has taken place but the The prfferred h g be Sublected to Cracking are conversion rate of cetane was only 6 percent those chiefly consisting of hydrocarbons with an open chain, for example alkanes, alkenes and alkylaromatic EXAMPLE 2 hydrocarbons, such as, for example, heptane, hexa- Example 1 has been repeated at 430C, thus resulting decane, eicosane, hexadecene and dodecylbenaene. In in a 40 percent conversion rate of cetane. The liquid contrast reactlon Prevalls Over products had substantially the same composition as in the crackmg reaction the cycloalkanes and the at example leastpartially saturated aromatic rings, for example cyclohexane and tetrahydronaphthalene. EXAMPLE 3 we claim: A light gas-oil of the following composition 1. A catalytic process for dehydrogenating a hydrodistillation T B P 20 percent at 255C carbon, said hydrocarbon being non-aromatic and at 50 percent at 280C least partiallysaturated with hydrogen, said process comprising dissolving catalyst and in said hydrocarbon in the liquid phase; and heating resultant mixture to 225-800 C. to dehydrogenate said hydrocarbon, said catalyst being a mixture of a compound of a metal selected from the groups lVa, Vla, Vlla and VIII of the periodic classification and a reducing agent selected from the group consisting of: I

a. a compound of the formula AlH X wherein n is l or 2, X when taken individually is OR, NR NHR or SR, R being a monovalent unsubstituted hydrocarbon radical or a hydrocarbon radical substituted by an ether group consisting of carbon, hydrogen and oxygen, and two X groups, when taken together, form an --AZ-B group in which A and B are alkylene radicals and Z is an oxygen or sulfur atom, an alkylene group, a NH group or a N- hydrocarbyl group, b. a compound of the formula ME[Al H X ,,,]p wherein m is l, 2 or 3, p is the valence of Me, Me is selected from the monovalent and divalent metals of groups la and lla, and the X groups are selected from the R, OR, NR NHR and SR groups when taken individually, and from AXB--- groups when taken by pairs, R being a monovalent unsubstituted hydrocarbon radical or a hydrocarbon radical substituted by an ether group consisting of carbon, hydrogen and oxygen; A and B being alkylene radicals and Z being an oxygen or sulfur atom, an alkylene group, a NH group or a N- hydrocarbyl group, 0. a compound of the formula AlR OR wherein R contains at least two carbon atoms and is a monovalent unsubstituted hydrocarbon radical or a hydrocarbon radical substituted by an ether group consisting of carbon, hydrogen and oxygen, and d. a compound of the formula AlR' wherein R is halogen or hydrocarbyl of 2-20 carbon atoms, with the provision that at least one R is said hydrocarbyl radical, the molar ratio of the reducing agent to the metal compound being in the range of from 0.5 to 20. 2. A process as defined in claim 1 wherein said reducing agent is (a).

3. A process as defined in claim 1 wherein said reducing agent is (b).

4. A process as defined in claim 1 wherein said reducing agent is (c).

5. A process as defined in claim 1 wherein said reducing agent is (d).

6. A process according to claim 1 in which the reducing agent has the formula Ali-l,,X,, in which n is l or 2 and X'is OR, R being alkyl of 2-20 carbon atoms.

7. A process according to claim 1 in which the reducing agent has the formula Me[AlH,,.X' in which m is l, 2 or 3 p is the valence of the metal Me, Me is lith ium or sodium and X is OR in which R is alkyl of l-20 carbon atoms.

8. A process according to claim 1, in which the reducing agent has the formula AlR OR in which R is alkyl of 2-20 carbon atoms.

9. A process according to claim 1, in which the reducing agent has the formula AlR in which R is alkyl of 2-20 carbon atoms.

10. A process according to claim 1, in which the catalyst is a mixture of cobalt stearate with the compound of formula NaAlH [O-tert.butyl] [O-tetrahydrofurfuryl].

' drocarbon is cracked during the dehydrogenating reaction.

14. A process according to claim 1, wherein the molar ratio of the reducing agent to the metal compound is from 1 to 6.

, drocarbon is a cycloalkane.

17. A process according to claim 1, wherein the hydrocarbon is a partially saturated condensed aromatic ring. 7

18. A process according to claim 1, wherein the metal compound is selected from the iron, cobalt and nickel compounds.

19. A process according to claim 1, wherein the metal compound is used at a rate of l to 1,000 parts by weight, expressed as metal, per million of parts by weight of hydrocarbon.

20. A process according to claim 1, wherein the reaction temperature is 300600C.

21. A process as defined by claim 1 wherein R is alkyl, cycloalkyl or aryl and contains l-20 carbon atoms.

22. A process as defined by claim 1 wherein R is alkyl of 2-20 carbon atoms.

I 'UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 3,773,657 Dated November 20, 1973 Inventor) Christian Lassau, et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

IN THE CLAIMS:

CLAIM 1, COLUMN 5, FIRST LINEET EOF "b" The formula "ME[A1 H X ]p" should reed Me [AlH X Signed and sealed this 16th day of April 1971+.

(SEAL) Attesti EDWARD I LFLETCHERQJR. C. MARSHALL DANN Commissioner of Patents Attesting Officer USCOMM-DC BO376-P69 FORM PO-105O (10-69) u.s. sovznuuzm' manna OFFICE: um Q-SGl-JM, 

2. A process as defined in claim 1 wherein said reducing agent is (a).
 3. A process as defined in claim 1 wherein said reducing agent is (b).
 4. A process as defined in claim 1 wherein said reducing agent is (c).
 5. A process as defined in claim 1 wherein said reducing agent is (d).
 6. A process according to claim 1 in which the reducing agent has the formula AlHnX3 n in which n is 1 or 2 and X is OR, R being alkyl of 2-20 carbon atoms.
 7. A process according to claim 1 in which the reducing agent has the formula Me(AlHmX''4 m)p in which m is 1, 2 or 3 p is the valence of the metal Me, Me is lithium or sodium and X'' is OR in which R is alkyl of 1-20 carbon atoms.
 8. A process according to claim 1, in which the reducing agent has the formula AlR2OR in which R is alkyl of 2-20 carbon atoms.
 9. A process according to claim 1, in which the reducing agent has the formula AlR''3 in which R'' is alkyl of 2-20 carbon atoms.
 10. A process according to claim 1, in which the catalyst is a mixture of cobalt stearate with the compound of formula NaAlH2(O-tert.butyl) (O-tetrahydrofurfuryl).
 11. A process according to claim 1, in which the catalyst is a mixture of nickel stearate and NaAlH(OC2H5)3.
 12. A process according to claim 1, in which the catalyst is a mixture of cobalt stearate and Al(iso-butyl)3.
 13. A process as defined by claim 1, wherein said hydrocarbon is cracked during the dehydrogenating reaction.
 14. A process according to claim 1, wherein the molar ratio of the reducing agent to the metal compound is from 1 to
 6. 15. A process according to claim 1, wherein the hydrocarbon is an alkane.
 16. A process according to claim 1, wherein the hydrocarbon is a cycloalkane.
 17. A process according to claim 1, wherein the hydrocarbon is a partially saturated condensed aromatic ring.
 18. A process according to claim 1, wherein the metal compound is selected from the iron, cobalt and nickel compounds.
 19. A process according to claim 1, wherein the metal compound is used at a rate of 1 to 1,000 parts by weight, expressed as metal, per million of parts by weight of hydrocarbon.
 20. A process according to claim 1, wherein the reaction temperature is 300*-600*C.
 21. A process as defined by claim 1 wherein R is alkyl, cycloalkyl or aryl and contains 1-20 carbon atoms.
 22. A process as defined by claim 1 wherein R is alkyl of 2-20 carbon atoms. 